blob: 1a97a5a844fdc228c3b9cd6b5e851c5faa3e029e [file] [log] [blame]
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package armasm
import (
"bytes"
"fmt"
"strings"
)
var saveDot = strings.NewReplacer(
".F16", "_dot_F16",
".F32", "_dot_F32",
".F64", "_dot_F64",
".S32", "_dot_S32",
".U32", "_dot_U32",
".FXS", "_dot_S",
".FXU", "_dot_U",
".32", "_dot_32",
)
// GNUSyntax returns the GNU assembler syntax for the instruction, as defined by GNU binutils.
// This form typically matches the syntax defined in the ARM Reference Manual.
func GNUSyntax(inst Inst) string {
var buf bytes.Buffer
op := inst.Op.String()
op = saveDot.Replace(op)
op = strings.Replace(op, ".", "", -1)
op = strings.Replace(op, "_dot_", ".", -1)
op = strings.ToLower(op)
buf.WriteString(op)
sep := " "
for i, arg := range inst.Args {
if arg == nil {
break
}
text := gnuArg(&inst, i, arg)
if text == "" {
continue
}
buf.WriteString(sep)
sep = ", "
buf.WriteString(text)
}
return buf.String()
}
func gnuArg(inst *Inst, argIndex int, arg Arg) string {
switch inst.Op &^ 15 {
case LDRD_EQ, LDREXD_EQ, STRD_EQ:
if argIndex == 1 {
// second argument in consecutive pair not printed
return ""
}
case STREXD_EQ:
if argIndex == 2 {
// second argument in consecutive pair not printed
return ""
}
}
switch arg := arg.(type) {
case Imm:
switch inst.Op &^ 15 {
case BKPT_EQ:
return fmt.Sprintf("%#04x", uint32(arg))
case SVC_EQ:
return fmt.Sprintf("%#08x", uint32(arg))
}
return fmt.Sprintf("#%d", int32(arg))
case ImmAlt:
return fmt.Sprintf("#%d, %d", arg.Val, arg.Rot)
case Mem:
R := gnuArg(inst, -1, arg.Base)
X := ""
if arg.Sign != 0 {
X = ""
if arg.Sign < 0 {
X = "-"
}
X += gnuArg(inst, -1, arg.Index)
if arg.Shift == ShiftLeft && arg.Count == 0 {
// nothing
} else if arg.Shift == RotateRightExt {
X += ", rrx"
} else {
X += fmt.Sprintf(", %s #%d", strings.ToLower(arg.Shift.String()), arg.Count)
}
} else {
X = fmt.Sprintf("#%d", arg.Offset)
}
switch arg.Mode {
case AddrOffset:
if X == "#0" {
return fmt.Sprintf("[%s]", R)
}
return fmt.Sprintf("[%s, %s]", R, X)
case AddrPreIndex:
return fmt.Sprintf("[%s, %s]!", R, X)
case AddrPostIndex:
return fmt.Sprintf("[%s], %s", R, X)
case AddrLDM:
if X == "#0" {
return R
}
case AddrLDM_WB:
if X == "#0" {
return R + "!"
}
}
return fmt.Sprintf("[%s Mode(%d) %s]", R, int(arg.Mode), X)
case PCRel:
return fmt.Sprintf(".%+#x", int32(arg)+4)
case Reg:
switch inst.Op &^ 15 {
case LDREX_EQ:
if argIndex == 0 {
return fmt.Sprintf("r%d", int32(arg))
}
}
switch arg {
case R10:
return "sl"
case R11:
return "fp"
case R12:
return "ip"
}
case RegList:
var buf bytes.Buffer
fmt.Fprintf(&buf, "{")
sep := ""
for i := 0; i < 16; i++ {
if arg&(1<<uint(i)) != 0 {
fmt.Fprintf(&buf, "%s%s", sep, gnuArg(inst, -1, Reg(i)))
sep = ", "
}
}
fmt.Fprintf(&buf, "}")
return buf.String()
case RegShift:
if arg.Shift == ShiftLeft && arg.Count == 0 {
return gnuArg(inst, -1, arg.Reg)
}
if arg.Shift == RotateRightExt {
return gnuArg(inst, -1, arg.Reg) + ", rrx"
}
return fmt.Sprintf("%s, %s #%d", gnuArg(inst, -1, arg.Reg), strings.ToLower(arg.Shift.String()), arg.Count)
case RegShiftReg:
return fmt.Sprintf("%s, %s %s", gnuArg(inst, -1, arg.Reg), strings.ToLower(arg.Shift.String()), gnuArg(inst, -1, arg.RegCount))
}
return strings.ToLower(arg.String())
}